DFTB+

DFTB+ performs atomistic quantum mechanical simulations using Density Functional based Tight Binding (DFTB) and extended tight binding methods to provide efficient approximate density functional theory (DFT) calculations for large systems.

Key Features:

• Density Functional based Tight Binding (DFTB): Implements the DFTB method for approximate DFT electronic structure calculations.
• Extended tight binding: Includes extended tight binding approaches to improve accuracy and transferability for larger systems.
• Approximation methods for excited states: Supports hybrid functionals and time-dependent formalism for excited-state simulations.
• Non-equilibrium Green's functions: Implements non-equilibrium Green's functions for electron transport calculations.
• Efficiency and scalability: Reduces computational cost compared with conventional ab initio DFT to enable large-scale and long-timescale simulations.

Scientific Applications:

• Materials science: Large-scale quantum mechanical modeling of materials including electronic properties and transport phenomena.
• Chemistry: Simulation of complex molecular interactions and reaction-relevant electronic structure using approximate DFT.
• Condensed matter physics: Investigation of electronic structure and electron transport in extended systems.

Methodology:

DFTB+ approximates DFT via the Density Functional based Tight Binding (DFTB) and extended tight binding approaches and supports hybrid functionals, time-dependent formalism, and non-equilibrium Green's functions for excited-state and transport calculations.